1. Field of the Invention
This invention concerns an arm especially useful in stall and stanchion dairy barns and the like for carrying a reader for a transponder worn by cattle. The arm is carried by a feed car which moves on a rail through the barn, with the arm placing the reader in close proximity to the transponder. The arm is advantageously constructed to yield in response to stationary objects and return to its original position to avoid injury to cattle and damage to the unit.
2. Description of the Prior Art
Animal husbandry has long been a labor intensive operation requiring an extraordinary amount of human labor in the care and feeding of the livestock. This has been particularly true of the dairy industry, which has required that the animals be milked, fed and maintained for optimum milk production. In recent years, the size of the herd of the average dairy operation has grown due to the economies of scale connected with the equipment and overhead costs.
The increased size of the dairy herds has been accompanied by a sophistication in the management of the herd for increased productivity. One of the advances which have occured as technology has advanced is the use of a feed car which can move from stall to stall of a feeding barn to deliver food to the cow. This has been accompanied by a recognition that each individual cow may have different feed requirements for either maintenance, calving or lactation. Thus, in order to maximize revenue, the dairy farmer must chart each of his cows in order to provide the optimum ration corresponding to the cow's milk production and nutritional requirements.
The feed car has thus served to reduce labor requirements and has recently been configured to provide a mixed ration for the cattle in the barn. That is to say, the feed car is equipped to deliver portions of grain, vitamins and minerals and other nutrients simultaneously in one combined feeding. The feed car has also been able to deliver an individualized ration so that each animal receives a customized mix of nutrients to satisfy his or her feed requirements. This has been accomplished in one of two ways.
The first method has been to have each customized ration fed to a specific stall. This has required that the cow be directed to the same stall for each feeding.
The alternative method has been to have each cow wear a transponder which identifies the cow for determining the ration it is to receive. A reader picked up the radio signal sent by the transponder and sent it to a computer where the ration was ascertained from the memory. The reader and transponder work together much like a bar code read by an optical scanner for many consumer products. The computer then signals the feed car to provide the appropriate individualized ration to the cow by discharging the selected nutrients programmed into the data base for that animal.
While this system has shown great promise for greater efficiency and management of the dairy herd, a chief drawback has been the expense associated with installation of a system capable of providing a reader at each stall in order to detect the signal transmitted by the transponder worn by each animal. Thus, a multitude of readers would be required and no suitable system has been developed for mounting a single reader to the feed car for reading the transponders.
A chief problem in developing a satisfactory reader arm is the requirement that the reader be placed in close proximity to the transponder in order to detect the signal. Each transponder has only a very short range to prevent a plurality of signals being simultaneously received by a reader.
A second problem associated with the first has been the need to orient the reader in a proper position to read the transponder worn by the animal.
A third problem has been to develop a reader arm which is yieldable to such obstructions as a stall stanchion or a cow's head to prevent injury to the animal or to the arm. The arm must be able to yield in a vertical as well as a horizontal plane, as a cow may step on the arm as it passes by.
Additionally, the arm must be self-centering so that upon yielding, it will return to its original position and will not continuously oscillate and thereby "slap" a cow after yielding to an obstruction.